Refrigeration apparatus



Sept. 5, 1939.

L. D. BURCH REFRIGERATION APPARATUS Filed April 10, 1930 2 Sheets-Sheet l BY E L INVENTOR. M M

ATTORNEY.

Sept. 5, 1939. 1.. D. BURCH 2,171,621

HEFRIGERATIQN APPARATUS Filed April 10, 1930 2 Sheets-Sheet 2 7 f [06 f a 1 4 as w a 3 o 0 I0 I! 48 3a 37 39 I INVENTOR.

7 42 43 L446 49 ATTORNEY.

Patented Sept. 5, 1939 UNITED STATES PATENT OFFICE B-l'llJSl REFRIGERATION APPARATUS Izwisl). Burch, Detroit,

alignmcn Mich. ulirnor, by meme Application April 10, 1930, Serhl No. 443,024

llclaims.

This invention relates to refrigeration apparatus, and has particular relation to refrigeration apparatus especially applicable either for domestic or commercial service.

Some of the objects of the invention are to dispense with the necessity for periodically defrosting the evaporating unit of a refrigeration apparatus; to avoid the drying out of moisture contained in articles disposed in the cooling compartment of a refrigerator; to increase the humidity in the cooling compartment of a refrigerator as compared with the degree of humidity heretofore prevalent in the cooling compartment of refrigerators; to provide for the reduction of the temperature of the cooling compartment of a refrigerator without incorporating therein cooling units having normal operating temperatures materially below the freezing point of water; to improve the appearance of the interior of a refrigerator by arranging the refrigerant evaporating unit externally of the refrigerator lining; to provide for the removal of condensed moisture from the interior of a refrigerator without employing unsightly vessels beneath the evaporating unit; to provide isolated cooling and freezing compartments in the interior of a refrigerator; to provide for the circulation of refrigerant liquid in an evaporating unit disposed substantially in a horizontal plane; to provide a refrigerant evaporating unit disposed externally of the cooling compartment of a refrigerator; to provide a removable refrigerating unit which does not extend into the interior of the cooling compartment of a refrigerator; to provide improved means for circulating cooling fluid over the various parts of a refrigerant condensing unit, and to provide in general a refrigerator which is more suitable for manufacture and distribution to the public than other refrigerators heretofore known.

The particular embodiment of the invention disclosed herein merely for the purpose of illustration, comprises generally a refrigerator composed of a plurality of insulated walls. an upper one of which is removable. A refrigerant condensing unit disposed in any suitable pofltion upon the upper surface of such removable wall, is provided with a tubular cover forming a stack in which heat dissipated by the condensing unit causes a circulation of air across the various parts of the condensing unit. Refrigerant liquid, supplied by the condensing unit. is discharged through an expansion valve of any suitable character into a refrigerant evaporating unit disposed beneath the removable wall of the refrigerator, and vaporized refrigerant from the evapcrating unit is also exhausted by the condensing unit during periodic operational cycles. The refrigeration system is so operated that the evapcrating unit will be retained at a relatively low 5 temperature in order that substances disposed in thermal contact therewith will be frozen rapidly.

The evaporating unit also is relatively isolated from the cooling compartment of the refrigerator 10 for the purpose of substantially preventing circulation of air therebetween and the consequent formation of frost on the evaporating unit. The cooling compartment is provided with a proper degree of refrigeration by associating therewith 15 a heat exchange device capable of absorbing heat from the cooling compartment at a relatively high rate. This heat exchange device is so associated with the refrigerant evaporating unit as to permit the flow of heat therefrom only 20 at a limited rate and consequently a relatively great temperature differential will be maintained between the device and unit. Notwithstanding the fact that the heat exchange device is retained at a relatively high temperature as 25 compared to the evaporating unit, it has a sufficient capacity to absorb heat from the cooling compartment that the latter is maintained at a proper temperature.

For a better understanding of the invention, 30 reference may now be had to the accompanying drawings forming a part of this specification, in which:

Figure l is a side view of a refrigerator embodying the invention, illustrated partly in ele- 35 vation and partly in cross section;

Figure 2 is a plan view of the refrigerator fllustrated by Figure 1, having a portion of the lid covering the latter broken away in order to disclose to view the parts therebeneath.

Figure 3 is a fragmentary front elevational view of the refrigerator illustrated by Figures 1 and 2.

Figure 4 is also a front view of the portion of the refrigerator illustrated by Figure 3, but hav- (5 ing a portion of the structure illustrated in cross section and having a removable portion of the structure elevated slightly.

A refrigerator cabinet I], employed in practicing the invention, comprises a pair of side walls II, a rear wall 12, and a front wall l3, all disposed in vertical planes and secured rigidly together at their edges. The bottom of the refrigerator is closed by a wall, not shown, similar to the aforesaid vertically disposed walls. All of 55 the walls are composed of some suitable insulating material such as cork or fibre board, and are reinforced by a suitable wooden frame ll, although a metallic or other suitable frame may be employed if preferred.

The outside of the vertically disposed walls of the refrigerator is covered with a suitable sheet metal casing 11. The front wall I3 is provided with an opening l9 through which access may be had to the interior of the refrigerator. A door I9, for the opening l8, consists of a frame 20 surrounding a piece of insulating material 2| and the front and back portions of the structure are covered by a metallic or other suitable sheets 22 and 23 having a space 24 between the edges thereof at the outermost extremity of the refrigerator door opening I 8. A refrigerator door gasket of any suitable character may be employed in this space if desired.

The entire refrigerator structure is suitably supported on a plurality of refrigerator legs or pedestals 23.

The interior of the refrigerator II is provided with a suitable metallic lining 21 which is secured to the front wall l3 of the refrigerator around the inner edges of the door opening III. A molding 29, composed of any suitable insulating material, is provided for the door opening II, in order to prevent the edges of the outer and inner metallic linings l1 and 21 respectively from being exposed to view.

The upper extremity of the cabinet Ill is closed by a removable wall 29 composed principally of insulating material of any suitable character. This wall is supported on a plurality of wooden or other suitable strips 3|, nailed or otherwise secured, to the walls H and I2 in such manner that the upper surfaces of the strips are spaced below the upper extremities of the wall a distance substantially equal to the thickness of the removable wall 29. An evaporator or vaporizer 32, spaced a short distance below the removable wall 29, is secured rigidly to the latter by spacing blocks 33 disposed at the corners of the evaporator and secured at opposite ends to the wall 29 and the vaporizer 32 by screws 39 and 36 respectively. The blocks 33 are preferably composed of any suitable material having a relatively low capacity for the conduction of heat.

While the evaporator 32 may be constructed in any preferred manner, as illustrated, it consists of a relatively flat metallic plate 31 in which a sinuously wound conduit 39 is embedded. The size of the plate is such as to divide the refrigerator into two substantially isolated compartments inasmuch as it so nearly approaches all of the walls of the refrigerator that the circulation of air between the compartments will be negligible. If perfect isolation of the compartments is desired, such may be realized by providing gaskets between the plate 31 and the walls ll, l2 and i3, and the door l9.

Below the evaporator 32, is disposed a heat exchange device consisting of a metallic plate 42, to the bottom portion of which a plurality of elongated U-shaped flns 43 are secured in spaced relation from front to rear of the cabinet. The plate 42 and fins 43 may be constructed as a unit by providing a plurality of projections II on the front and rear edges of the plate which may be bent downwardly between the upper bent extremities of the fins for securing them rigidly against the plate. A good metallic contact between the plate and fins then may be provided by welding the parts together or by dipping the entire heat exchange unit in tin, galvanized iron or other suitable solidifying metal. The heat exchange device II is supported on the upper wall 46 of the inner metallic lining 21 on suitable strips 41 disposed therebetween and in such manner that the upper surface of the heat exchange unit will be slightly spaced from the lower surface of the evaporator 32. This space may be filled by a suitable sheet of insulating material 49 or it may be left open if preferred, thus relying on the insulating characteristics of a space filled with a relatively isolated quantity of air.

It is quite well known that the greater the external surface of an evaporator, the greater will be the capacity of such evaporator to produce refrigeration. In other words, an evaporator having a relatively large amount of external surface will absorb heat from a refrigerated chamber in which it is located at a greater rate than an evaporator with a small external surface. The difference between the temperature of the evaporator and the temperature of the compartment in which it is located is generally known as the evaporator and refrigerator differential. Naturally, with an evaporator having a large amount of external or heat absorbing surface, the temperature differential would be relatively small, and consequently if the evaporator be maintained at a temperature low enough to produce freezing of water at a relatively rapid rate, the refrigerator temperature will be likewise relatively low.

Since such low temperature in a refrigerator cooling compartment is not desirable under all circumstances, it has been customary heretofore to employ an evaporator having only a limited amount of external or heat absorbing surface, under which circumstances the temperature of such limited amount of heat absorbing surface had to be relatively low in order to cool the refrigerator cooling compartment to the desired extent. This naturally resulted in freezing out of the moisture contained in the atmosphere of the cooling compartment, and consequently in a reduction in the humidity therein to such an extent that vegetables or other articles of food placed in the cooling compartment gave up their moisture rapidly, and became so withered or wilted in a short time, as to be unsuitable for use.

Now, the present invention contemplates avoiding this dangerous reduction in the humidity of a refrigerator cooling compartment, by providing a heat exchange device ll having a relatively large amount of heat absorbing surface which is so disposed with respect to a refrigerant evaporating unit that its temperature will not be reduced to such an extent that frost will be formed thereon. In other words, the temperature of the heat exchange device will be relatively high as compared to the evaporating unit, and consequently a large temperature differential will be maintained. A large amount of heat exchange surface at a high temperature, however, will maintain the cooling compartment of a refrigerator at a proper refrigerating temperature just as well as a small amount of heat exchange surface at a relatively low temperature.

In the present instance, therefore, the heat exchange device Ii is provided with surface of such extent that its temperature can be retained either part or all of the time above the freezing point of water, and yet properly cool the cooling compartment of the refrigerator. At the same time, the evaporator 32 may be retained at any desired low temperature by varying the resistance to the flow of heat between such evaporator and the heat absorbing device 4|.

In order to provide for the proper circulation of air in the refrigerator cooling compartment, the lower extremities of the-fins 43 are slightly inclined with respect to a li orizontal plane in order that a greater amount of refrigeration may occur in one portion of the compartment than in another. The upper wall of the refrigerator lining 21 is likewise inclined in parallel relation to the lower extremities of the fins 43, and openings 4! and I! are provided in the wall ll at the upper and lower extremities thereof respectively. It is apparent that warm air will enter the opening 48 and by coming in contact with the heat exchange device ll, will be cooled to such extent that it will flow downwardly along the surface of the fins 48 and outwardly through the open ing 49. In this manner a constant circulation of air, and a proper cooling compartment temperature, is maintained.

The refrigerator lining 21 alsois provided with another opening II in the portion thereof imniediately in front of the opening between the evaporator 32 and the refrigerator wall 28. Through this opening freezing trays 52 may be inserted into or removed from a freezing compartment therein.

While the temperature of the heat exchange unit II will not be low enough to cause the formation of frost thereon, there will be a certain amount of condensation of moisture on the surface of the fins 43, and the lower surface of the plate 42, but the capillary attraction between the moisture and the surfaces is great enough to prevent the moisture from falling off of the heat exchange device at any points except where it collects at the lower extremities of the flns 43. Therefore, in order to prevent moisture from falling through the openings .8 sand", it may be desirable under some circumstances to cut notches in the fins 43 above the openings, thus providing the portions of the flns above the openings with a greater degree of inclination than the other portions. This increased inclination will decrease the tendency of the moisture total] from the lower extremities of the fins in such regions and permit it to flow to lower points beyond .upwardly projecting flanges formed in the lining around the openings.

The refrigerator walls above the lining I! may be protected from damage due to moisture, by any suitable lining, such as a coating of waterproof asphalt paint or compound 54 which, atthe lower extremity thereof, seals the upper extremity of the refrigerator lining 21 and the outer walls of the refrigerator to prevent moisture from flowing downwardly therebetween. The moisture is collected at the lower extremity of the space above the wall 46 of the lining 21 and conducted downwardly outside the lining 21 through a. conduit 58 communicating at the bottom of the refrigerator III with a drip pan i1 removably secured thereto in any suitable manner.

The evaporating unit 32 may be supplied with a refrigerant liquid by any suitable refrigerating system, but, as illustrated, a compression condensation expansion type of system is employed. In this system the refrigerant liquid may be expanded into the evaporating unit in any suitable manner, as, for example, by the employment of a high side float valve 50. This valve embodies a float chamber Si in which refrigerant liquid is discharged and from which flow is controlled by a float actuated valve 02. The refrigerant liquid passes from the high side float I! through a conduit I! and into a refrigerant reservoir '4 positioned in the space between the evaporator 32 and the wall II at the rear extremity thereof.

The refrigerant evaporating passage, formed by the conduit ll embedded in the plate 31, is connected at different extremities to the interior of the reservoir 44 by a pair ofconduits "and I. The conduit 6 is somewhat larger than the conduit I1 and is connected to a lower extremity of the reservoir 60. The smaller conduit 61 terminates in the reservoir I4 in a region maorated in the evaporating unit II, it is apparent that' some of the bubbles formed by the refrigerant vapor will tend to flow into each of the conduits it and ll. Due to the difference in the size of the conduits, however, there will be a greater concentration of the refrigerant bubbles in the conduit 61 than there will be in the conduit '6. All of the bubbles tend to pass upwardly into the reservoir II, and since there is a greater concentration of bubbles in the conduit 61 than there is in the conduit 66, there will be a greater tendency to push the liquid in front of them in the conduit 81 than there will be in the conduit 66.

Also, the difference in the concentration of bubbles in the conduits causes an actual diiference in the liquid hydrostatic head therein by reason of the fact that the bubbles displace a greater proportion of the liquid in the conduit 61 than they do in the conduit 06. It is apparent that these two effects of vaporization of refrigerant in the evaporator 32 result in a greater tendency for liquid to flow downwardly in the conduit 6i than there is for it to flow downwardly in the conduit 61. Such tendency of the liquid to' flow downwardly in the conduit 66 opposes the flow of bubbles upwardly through such conduit and causes them all to pass through the evaporating unit and out through the con duit U. The presence of all of the bubbles in the conduit 81, of course, increases the tendency for liquid to circulate downwardly through the conduit 6, and consequently increases the rate of circulation in the entire unit.

It is apparent that the greater the difference between the vertical length of the conduits or the difference between their diameters, within reasonable limits, the greater will be the force tending to produce circulation in the evaporator unit I2.

The amount of refrigerant liquid employed in the system is such that a substantial vapor space will always be maintained in the receptacle 64 above the level of the liquid therein. A suction conduit i8 is connected to the receptacle N in such manner that the end of the conduit terminates in the receptacle above the level of the liquid therein. The opposite end of the suction line it is connected to an opening in a motor compressor unit casing 89 and the opposite end of the opening communicates with an inlet port for the compression space of a rotary pump II.

The present invention does not depend on the employment of a particular type of pump such as that indicated by the numeral II; this one having been selected merely as being well known in the art and suitable for the purpose sought to be served.

The casing 60 preferably is of cylindrical formation with its axis extending in a direction perpendicular to the upper wall 20. Vertically disposedflnsfl areformedonthe casing I and project outwardly in a radial direction thereabout. The width of the fins at the top is greater than that at the bottom portions thereof. The casing is provided with heads II and II secured to the upper and lower extremities thereof by bolts 16 thus closing the cylindricalopening formed therein. The head ll restson the upper surface of the removable wall I! and the entire motor compressor structure is secured to and removable with the wall.

The casing 69 also is provided with a transversely projecting wall or web I4 having an upwardly projecting flange I8 formed centrally thereof for the reception of a sleeve portion II of a cylinder end plate 18. The sleeve ll provides a bushing for a journal bearing in which a common shaft II, for a motor I! and for the compressor ll, rotates.

The lower end of the shaft is provided with an eccentric 81 surrounded by a compressor rotor 84 having a blade, not shown. projecting therefrom, which blade is so mounted as to permit oscillation thereof in a radially formed opening in a plate 86 having a cylindrically formed opening therein for the reception of the rotor 84. The diameter of the opening in the plate 86 is substantially equal to the greatest possible distance between the outer surface of the rotor 84 and the axis of the shaft Ill. The widths of the eccentric II, the rotor 84 and the plate 86, are substantially equal, in a direction parallel to the axis of the shaft II.

An end plate I! abuts the lower extremities of the eccentric II, the rotor 84 and the plate It. and is secured through the latter and the end plate 19 to the web ll by bolts 88. The plates 81, 86 and Ill all are provided with annular flanges 89 projecting outwardly therefrom into engagement with a cylindrical projection 9! extending from the lower surface of the web 14. The extension Si is provided for the purpose of enabling the several elements of the pump to be centered properly relative to the axis of the shaft ii. The upper extremity of the shaft 1| above the web 14 is secured rigidly in an opening formed axially through a rotor 02 of the electrical motor 02. The field coils ll of the motor I! are suitably associated with a laminated metallic stator M which is secured to and supported by an upper portion of the casing 63.

The compressed refrigerant fluid is discharged from the compressor ll through a discharge port controlled by a reed type discharge valve 86 located in the interior of the casing 69 above the web ll. The discharge and inlet ports to the cylinder are located on opposite sides of the foresaid blade projecting from the compressor rotor 84. Rotation of the eccentric therefore causes fluid to be compressed in the cylinder between these ports.

The compressor H is adapted to run substantially immersed in a quantity of oil retained in the casing 69 below the web II. The upper and lower portions of the casing communicate through an opening 91 which permits oil to return from the upper portion of the casing to the lower portion.

It is well known that there are three sources from which heat dissipated by a refrigerant condensing unit, of the type illustrated, is derived. There is heat due to losses in the electric motor and friction of all of the moving parts of the apparatus; heat generated by the force exerted a,171,ea1

in compressing the refrigerant fluid; and heat transferred from the interior to the exterior of' a refrigerator by the operation of the condensing unit. Now, in most refrigerating mechanisms, the heat removed from the refrigerator is only about one half of the total quantity of the heat dissipated by the condensing unit. and consequently only this amount of heat must necessarily be dissipated at a temperature which will permit the condensation of refrigerant fluid. The remainder of the total heat dissipated by the condensing unit may be dissipated at any temperature desired and the higher such temperature is, the lesser will be the surface required to dissi- Date it.

In the present instance, all of the moving parts of the refrigerating mechanism are contained in a single easing into which all of the compressed fluid from the compressor is discharged. This fluid is immediately superheated by the addition thereto of the sum of the quantities of heat generated due to the motor losses and friction, and the work done in compressing the refrigerant fluid. This superheating of the gas in the casing 69 does not permit the condensation of liquid in such casing. although the vapor pressure therein may be such that if the liquid were not superheated, it would condense.

Since the space in the interior of the casing is relatively large in proportion to an outlet provided therefor, and since the casing is provided with fins H for materially increasing the heat radiating surface thereof, an amount of heat equal to the total heat dissipated by the condensing unit minus the heat removed from the refrigerator is dissipated by the casing 69 and fins 12 at a temperature much higher than the temperature required for the condensation of refrigerant fluid at that pressure. By reason of the dissipation of such quantity of heat at a relatively high temperature, it is apparent that a much smaller amount of heat radiating surface is required than would be required if such quantity' of heat were dissipated at the lower temperature at which liquid that is later evaporated in a refrigerator, must be condensed.

Due to the high temperature of.the casing 69 and fins 12, the air which comes in contact with such parts will be heated to a relatively high degree, and consequently will tend to rise rapidly.

In order to increase the velocity of the ascending air surrounding the casing 69 and fins 12, an efficient stack 99 is disposed closely about the outer extremities of the flns 12 in order to prevent cooler air from being drawn into the ascending column between the upper and lower extremities of the heat dissipating elements. Consequently all of the air admitted to the stack must traverse substantially the entire length of the fins 12 and casing 68 and consequently will be heated to a higher degree than otherwise would occur. The higher the temperature of the air in such stack, the higher will be its velocity therein, and consequently a large number of cubic feet of air per unit of time will be conveyed through the stack.

The aforesaid restricted discharge opening from the casing 89 is connected to a suitably finned condenser "II in which the dissipation of heat occurs at a temperature low enoughto condense liquid therein. This condenser is located at the lower extremity of the stack 99 and consequently all of the air traversing the stack passes over the condenser at room temperature. All of the heat added to such column of air passing thereover, which quantity is stantiaily equal to the heat removed from the refrigerator, is added to the stack at the bottom thereof, and consequently such heat exerts the maximum possible influence on the average temperature of the rising column of air in the stack. By so arranging the stack and condenser, it is necessary to employ only a relatively small amount of heat exchangesurface on the condenser iili in order to obtain the dissipation of a sufficient amount of heat to condense the liquid required in the operation of the refrigeration system. The refrigerant liquid, whe condensed in the condenser IM passes to the hi h side float 59 through the conduit III connected therebetween.

The stack 99 preferably is constructed by forming a frusto-conical dome in a sheet metal cover I03 employed as a top for the cabinet II. The upper extremity 'of the dome forming the stack 99 is provided with a plurality of openings I to permit cooling fluid to be discharged from the stack. An inlet passage to the stack 99 is provided by mounting the cover III! on a pinrality of radially disposed strips llll located on the upper surface of the cabinet ll. The outer extremity of the cover is rolled downwardly and inwardly as indicated at I" in such manner that the lower extremity of the cover is spaced from the cabinet, as indicated at ill], in order to permit cooling fluid to circulate upwardly through such opening, across the top of the cabinet it, across the condenser Ill, through the stack 99 and out through the openings i.

It is apparent that any suitable form of control mechanism, not shown, may be employed for the purpose of causing cyclic operation of the refrigerating mechanism illustrated herein.

As will be noted from Figure 4, the entire refrigeratirig mechanism is removable from the cabinet ill by reason of the construction of all of the parts above and including the evaporator 32 as a single unit. The cover I03 may, however, be assembled independently either of the cabinet or the removable mechanism unit, and consequently may be taken off independently in order to inspect the mechanism of the condensing unit .without removing it from the cabinet. When the mechanism unit is removed, it is apparent that the heat exchange device I, associated with the cooling compartment or refrigerator proper, remains with the cabinet ill.

It will be apparent to those skilled in the art that the structure disclosed herein is merely illustrative of the invention and that many modifications and changes may be made in such structure without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. A refrigeration apparatus comprising a plurality of heat insulated walls forming a cooling compartment, a metallic refrigerator lining in such compartment, said lining having an upper wall disposed in an inclined relation to a horizontal plane, a plurality of fins above said inclined wall, a passage for circulating air between the iins and the interior of the aforesaid refrigerator lining, and means for absorbing heat "from the aforesaid fins.

9,171,621 subrefrigerated iins extending across the opening above the lining, and means for preventing condensed vapor from falling by gravity from the fins through the opening.

3. A refrigeration apparatus comprising a plurality of heat insulatedwalls forming a cooling compartment, a heat exchange device disposed within said compartment, said heat exchange device being provided wtih a plurality of metallic fins having the lower edges thereof disposed in an inclined relation to a horizontal plane and the upper edges thereof disposed on a horizontal plane.

4. A refrigeration apparatus comprising a plurality of heat insulated walls, a fixed metallic refrigerator lining disposed interiorly of the walls to provide a cooling compartment, a refrigerant evaporator disposed within said walls but externally oi' the confines of said lining, said lining being open for the passage of air from the compartment in heat exchange relation with the evaporator and means for the insertion of a freezing tray through the lining into thermal contact with the evaporator.

. 5. A refrigeration apparatus comprising an insulated cabinet having an upper removable wall, a refrigerator lining for the cabinet, said lining having an aperture formed therein and a refrigerant evaporating unit supported by the removable wall externally of the aforesaid refrigerator lining and accessible from the interior of said lining through said aperture.

6. A refrigeration apparatus comprising an evaporating unit having a horizontally disposed header disposed above the evaporating unit, means for maintaining the header partially filled with refrigerant liquid, a relatively small conduit for connecting one portion of the passage in the evaporating unit with an upper portion of the header, and a relatively large conduit for connecting another portion of the passage in the evaporating unit with a lower portion of the header.

'1. A refrigeration apparatus comprising a cabinet having a refrigerant condensing unit mounted externally thereof, and a cover for the cabinet having a stack formed therein for receiving the condensing unit, said cabinet and cover being provided with means to permit the circulation of cooling fluid from beneath the edge portion of the cover to the stack.

8. A refrigeration apparatus comprising a pinrality of heat insulating walls, a plate evaporator disposed in spaced relation to one of said walls to provide an ice freezing compartment, a heat exchange device associated with said plate evaporator, but independent of the refrigerant circuit therein, and a relatively thin sheet of heat insulating material disposed between the evaporator and heat exchange device for restricting the conduction of heat therebetween.

9. A refrigeration apparatus comprising a plurality of walls arranged to form an insulated compartment, one of said walls being removable, a plate refrigerant evaporator disposed in spaced and parallel relation to said removable wall and supported thereby, a filled heat exchange device disposed in space relation to said plate and a partition separating said plate and heat exchange device from the remainder of said insulated compartment, said partition being provided with apertures for rendering the evaporator and finned heat exchange device accessible from beyond the partition.

10. A refrigerator cabinet comprising insurality oi heat insulatedwalls forming a cooling compartment, a refrigerant evaporator, a neat exchange'device associated with said evaporator for cooling said compartment, said device being spaced from said evaporator to provide a predetermined fixed temperature differential between the evaporator and a surface of said heat exchange device, and fins in metallic contact with said surface 01' said device and extending away from said evaporator.

LEWIS D. BURCH.

CERTIFICATE OF CORRECTION Patent No. 2,171,621.

September 5, 1959.

LEWIS D. BURCH.

It is hereby certified that error appear-sin the printed specification of the above numbered patent requiring correction as follows: Page 5, first column, line ID, for "sand" read and; page L, first column, line 58-59, for "foresaid" read aforesaid; page 5, second column, line 9, claim 5 for "wtih" read with; line 5b,, claim 6, after "disposed" insert passage for evaporating refrigerant liquid, a;,1ine 67, claim 9, for the word "filled" read finned; and that the said Letters Patent should be readwith this correction therein that the same ma conform to the reggrd of h case in the Patent Office.

Signed and sealed this lhth day of November, A. D. 1959.

(Seal) Henry Van Arsdale,

Acting Commissioner of Patents.

rality oi heat insulatedwalls forming a cooling compartment, a refrigerant evaporator, a neat exchange'device associated with said evaporator for cooling said compartment, said device being spaced from said evaporator to provide a predetermined fixed temperature differential between the evaporator and a surface of said heat exchange device, and fins in metallic contact with said surface 01' said device and extending away from said evaporator.

LEWIS D. BURCH.

CERTIFICATE OF CORRECTION Patent No. 2,171,621.

September 5, 1959.

LEWIS D. BURCH.

It is hereby certified that error appear-sin the printed specification of the above numbered patent requiring correction as follows: Page 5, first column, line ID, for "sand" read and; page L, first column, line 58-59, for "foresaid" read aforesaid; page 5, second column, line 9, claim 5 for "wtih" read with; line 5b,, claim 6, after "disposed" insert passage for evaporating refrigerant liquid, a;,1ine 67, claim 9, for the word "filled" read finned; and that the said Letters Patent should be readwith this correction therein that the same ma conform to the reggrd of h case in the Patent Office.

Signed and sealed this lhth day of November, A. D. 1959.

(Seal) Henry Van Arsdale,

Acting Commissioner of Patents. 

